Fuel injection pump



Patented Mar. 31, 1953 flpbertAuLasley-phibago, Ill., assignor, by mesneassignments; toyliouisfi. Simmnngflhicagmjll. Annlihaztiumseptemherzl,r948; serialcNo..5p;zg-'1 (Cl. mar-2.02

ro ;,isproyided;.wit ventaholeszinathez i o reventing @mpression:clients;- P. ody.- pening.uu mrl cipizocaethan tonzlandizspringtcum"Iluesztorzthe; eu eder oned imfllela niieetiomimlmps; Y .4 ilfpast-the-pistom inevitable and fuel oil 7 gleakmsefromzztheapumpsescapesithroush th=3V$Jl1;1hO1eS in the spring cup. In order to preventobjectionable dilution of th lu atinsroiii f theen ineers; the fuel oileaka e, at empts have..heen,madestotcollectlth fuel oil" as it isdischarged 'from rthesspring cupg vent-holes in an annular receptaclesurrounding the push rod irrthe enginebloek -openings, but such attemptshave not m ith sucoesseduee aree xz o hez aet thett a-h speed reeiproeaefth pus damlwthe- .umumistomoauses mpin econztheepushgodsend h. o lthuseolleetin ,omtheipusmrod woman's We on .thee ushirodandintosthelubricatin ils t he eua ne,-.

Furthena erupts torpneventthisgobjectionable QhfillfiiQhhhWhyolveclflthe 111serof-3 splaslrguards or baflles of generally umbrellashape carried by the push rod, butsuch expedients likewise have not beensuccessful because of the tendency of the leakage-oil collecting on thelower edge of the umbrella to work its way up the under' side of theumbrella and onto the push rod during reciprocation of the parts. It isa further object of this invention, therefore, to provide in a fuelinjection pump an improved spring cup construction for insuring that thefuel oil leakage from the pump is effectively conducted to thereceptacle therefor, whereby dilution of the lubricating oil of theengine is minimized. i In carrying out the invention in one form aoflthi s n peotivelyz pntain ngean.. mendin -fi d pump; of: the; clasmdescribed provided-. with a sprin cup; in; Whifihn vent;h01es; areformed. in"; the; bottom: wall. immediately adjacent.- the outer edge?thereoii and: a: cylindrical.- sleeve extending;

from the bottom wall and disposed inwardly of the; vent holes; is:provided for: guiding; into: areceptacle;thefuel1oilrleakagesdischarged' through.- the vent; holes;the: sleeve being, of. greater. length. than; theg-axial displacement;of thesspring,

cup during; operation: oft. the pump For more; completeunderstanding;of; the in!" vention" reference should: now; be. had. to. the; drawingin: which t the; single; figure; is an e1e. va'.--= tional view; of;atfuelfiinjectiom pump; embodying;

they presentinvention; mounted, on; an. engines block, a p0rtion..of-:.theipump, and-thev bloclo. be:- ing; sectioned-1 along; the; axial.center: line; of: the: pump moteiclearly; to; illustrateetheconstruction;

Referring nowl totha-drawing;.theeinventiong-is shownasembodiediimaefueltiniectionpumpthavi gfpumn; body -zl 0'.- providedwith an; annular: ex ternal flan e :1 Lby means of.iwhichstheipumpimaybeasecured-zto,the:.engineb10ck.; l 2 by; suitable'voap boltss(not;.-sho.wn) t he: pump: body? I01 and. the: engines block; l2; being;provided;-: with aligned; openings; l'3- and.' 14;,respectively:Theiifuel injectionvpumpg,iissofeaatyp'e.generallytknown nithe artsanddncludes a; cylindertbarrele I-Se; the-flower:- endqof; which extendsintofv thezlopening l3- and; a. recip ro.catableipistoml 6, theg-lowerend. of which extends from.-. the. cylinder barret 5,1, as;shown; Thee P1 1 11; is: of thei. type';in.. wh1ch: they; pump? function:iSz'iEtGhiGVEd .-by.;-thezreciprocating; move?" menta-of the-2 pistom Ilip-and.- the amount of? :fuel'i deliyered in eachstrokeqiseadjustedbyirotationof the piston, |6:i1'l-. the icylinderxbarrel't The manner inwhich the rotation Oi'TthEDi'StOIII-J is utilizedto 'controluthe-amountof; fuel delivered by the pump; will: bet. well understood--. by; those:

skilled; int. the. art. and; no detailed; explanation:

iss thoughttto; be .-.necessary; other; thanjtot. points. out that alongitudinally movable rack 11 is arranged to effect rotation of asleeve [8 having a slot l9 adapted slidably to engage an upstandingfinger 20 extending from a collar 2| which is rigidly secured to thepiston IB. Adjacent its lower end the piston I6 is provided with a head22 for receiving a spring retainer 23 adapted to be engaged by the lowerend of a spring 24, the upper end of which bears against a springretainer or washer 25 arranged to engage a suitable shoulder 26 formedin the pump body (0.

Surrounding the spring 24 and the lower end of the piston I6 is a springcup 21 which slidably engages the walls of the pump body forming theopening l3. The bottom wall of the spring cup 21 engages the lower endof the piston l6 and the spring retainer 23 and is in turn engaged by anoperating member or a push rod 28 which is adapted to be reciprocated intimed relation to the engine by suitable engine driven means (notshown). Disposed within the opening 14 in the engine block l2 andsurrounding the push rod 28 is a guide 29 which is formed as shown toprovide an annular channel or receptacle 30 surrounding the push rod. Itwill be understood that suitable outlet or drainage means (not shown)are provided for withdrawing from the annular receptacle 30 any fuel oilwhich accumulates therein.

During operation of the pump piston 16 by the push rod 28 the sprin cup21 reciprocates in the opening l3 at high speed and in order to preventcompression efiects within the opening l3 of the pump body the bottomwall of the spring cup 27 must be provided with vent holes. Inaccordance with the present invention a series of vent holes 31 areprovided disposed adjacent the outer peripheral edge of the bottom wallof the spring cup.

Although the piston 16 of the fuel pump is provided, in accordance withthe usual practice, with a plurality of sealing grooves 32, it will beunderstood that oil leakage past the piston is inevitable under the highpressures developed by the pump and it will be apparent that such oilleakage will be discharged through the vent holes iii in the bottom wallof the spring cup 21. The vent holes 3| are disposed, as shown,immediately above the annular receptacle 30 and in order effectively toguide the oil leakage into the receptacle even though'the spring cup isreciprocating at high speed, a cylindrical sleeve 33 is provided,extending downwardly from the bottom wall of the spring cup, the sleeve33 being disposed inwardly of the vent holes 3|. The length of thesleeve 33 exceeds the stroke of the pump and the push rod 28' andconsequently oil leakage accumulating on the lower edge of the sleeve 33cannot workits wayup the inner surface of the sleeve 33 to such anextent as to reach the push rod 28. Consequently the fuel oil whichleaks from the pump and is discharged through the vent holes 3| will besubstantially entirely confined to the receptacle 30 and dilution of thelubricating oil of the engine is avoided. While the sleeve 33 has beenshown as having been formed'integrally with the'spring cup 21 it will,of course, be understood that this sleeve may be made as a separate partif desired and secured to the bottom wall of the spring cup in anysuitable fashion.

While a particular embodiment of the invention has been shown, it willbe understood, of course, that the invention is not to be limitedthereto, since many modifications may be made.

4 and it is contemplated, therefore, by the appended claims, to coverany such modifications as fall within the true spirit and scope of theinvention.

What is desired to be secured by Letters Patent of the United States is:

1. A spring cup for a fuel injection pump of the class described, saidspring cup having a vent hole in the bottom wall thereof disposedadjacent the outer edge of said bottom wall and a cylindrical'sleeverigid with said cup extending from said bottom wall and disposedinwardly of said vent hole for guiding fuel leakage from said pumpdischarged from said cup through said vent hole.

2. A spring cup for a fuel injection pump of the class described, saidspring cup having vent holes in the bottom wall thereof disposedadjacent the outer edge of said bottom wall and a cylindrical sleeverigid with said cup and extending from said bottom wall disposedinwardly of said vent holes for guiding fuel leakage from said pumpdischarged from said cup through said vent holes, said sleeve beingmovable with said cup and having a length greater than the axialdisplacement of said spring cup during operation of said pump.

3. A spring cup for a fuel injection pump of the class described, saidspring cup having vent holes in the bottom wall thereof disposedadjacent the outer edge of said bottom wall and a cylindrical sleeverigid with and extending from said bottom Wall immediately adjacent andinwardly of said vent holes for guiding fuel leakage from said pumpdischarged through said vent holes.

4. A spring cup for a fuel injection pump of the class described, saidspring cup having vent holes in the bottom wall thereof disposed ad:jacent the outer edge of said bottom wall and a cylindrical sleeve rigidwith said cup and extending from said bottom wall immediately adjacentand inwardly of said vent holes for guiding fuel leakage from said pumpdischarged through said vent holes, said sleeve being longer than thestroke of the pump.

ROBERT A. LASLEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 2,414,267 Meitzler Jan. 14, 1947

